The disclosed subject matter relates generally to techniques for converting signal and idler photons generated by a nonlinear optics into a deterministic stream of single photons.
Single-photon sources are utilized in a number applications, including quantum information science, quantum computing/simulation, quantum cryptography/quantum key distribution, quantum teleportation, precision measurements and sensing, tests of quantum nonlocality, and high resolution lithography. For example, complex nonclassical optical states required for quantum metrology can be constructed from single-photon sources. Additionally, nondeterministic logic operations between multiple photonic qubits, combined with the ability to detect when gates have succeeded (feed-forwardability), can allow for efficient quantum computation.
To realize these and other quantum information technologies, efficient sources of indistinguishable single photons are useful. Certain techniques for generation of indistinguishable single photons include the application of quantum dots in micro- and nano-cavities, isolated cold atoms, and isolated single molecules in solid-state systems. However, they can require complex setups, including high vacuum and cryogenic temperatures, not immediately suitable for scalability.
While spontaneous parametric down conversion can produce highly indistinguishable single photons, generation is nondeterministic. Techniques for the generation of on-demand single photons using spontaneous parametric down conversion can be large and expensive, employing bulk optics. Moreover, such techniques can employ photon capture schemes that suffer from high loss, particularly when scaled up.
Accordingly, there is a need for an improved technique to provide sources of indistinguishable, on-demand single photons.